01Product

L-Leucine

At a glance

L-Leucine from Zhicheng Bio — supply summary

Zhicheng Bio supplies bulk L-Leucine, CAS 61-90-5, shipping from Shanghai, China. This grade is produced to order. Every shipment carries a batch Certificate of Analysis; specification sheet and MSDS are supplied on request. Sourced to order — about 1 week to Shanghai port. Zhicheng Bio publishes no list price — quotes are issued per quantity and Incoterm by email to zhicheng1@zhicheng-bio.cn.

Supplier: Zhicheng Bio, Shanghai, China
CAS number: 61-90-5
Molecular formula: C6H13NO2
Availability: Made to order
Documents: Batch CoA with every shipment; spec sheet and MSDS on request
Packing: 25 kg cartons or bags, adjustable
PubChem CID: 6106
How to get a price: Email RFQ to zhicheng1@zhicheng-bio.cn — no list price is published

BCAA / EAA ~1 week

L-Leucine

CAS 61-90-5 · C6H13NO2

Bulk L-Leucine for B2B manufacturing — supplied against your target specification, with documentation your QA can review before anything ships. Pricing below is indicative; send an RFQ for a firm quote, MOQ and lead time.

$6.79 – $7.61 /kg by order volume · indicative, ex-Shanghai

Indicative range — larger volumes price toward the low end. Ingredient markets move weekly; your firm price is confirmed by quotation, typically within one business day.

Category: BCAA / EAA

Availability: Sourced to order — about 1 week to Shanghai port

Packing: 25 kg bags, cartons or drums (standard)

Key supply points

Supplied against your target specification — USP / FCC / JP monograph where applicable
Recent batch COA provided with the quotation, before you commit
Consolidates with other SKUs into one shipment out of Shanghai
Third-party lab verification available pre-shipment on request

Documentation with every batch

COA per batchSpec SheetMSDS / SDSExport docs

Third-party lab verification can be arranged pre-shipment on request. Certificates of origin, non-GMO or allergen statements per destination-market requirements.

Request COA & Quote Use the RFQ form

Shipping & Lead Time

Estimate freight for this product

~1 weekSourced to order — about 1 week to Shanghai port

Destination region Quantity (kg)

Air FreightFast

Transit: —
Est. freight *: —
Total door-to-port: —

Sea LCLValue

Transit: —
Est. freight *: —
Total door-to-port: —

Request Exact Quote

Documentation-first

COA per batch, Spec Sheet and MSDS — reviewed by your QA before anything ships.

Ready-stock depth

Multi-tonne inventory on core SKUs, plus 28 actives held in our US warehouse in Los Angeles for domestic delivery.

Certified supply chain

Sourced from audited, certified manufacturers — ISO, HACCP, Halal & Kosher available.

Flexible export

25 kg bags, cartons or drums; FOB / CIF / DDP by lane, sea or air consolidation.

02Identity & properties

Identity & properties

Compound identifiers and physical properties for this material. The binding version is always the Specification Sheet and batch COA issued with your quotation.

CAS No.	61-90-5
Molecular Formula	C6H13NO2
Molecular Weight	131.17
EINECS	200-522-0
Synonyms	L-Leucine, L-Leu, L, (2S)-2-amino-4-methylpentanoic acid
Appearance	White glistening hexagonal plates or crystalline powder, odourless
Solubility	Water 24.26 g/L at 25 °C (Merck series: 22.7 g/L at 0 °C, 24.26 at 25 °C, 28.87 at 50 °C, 38.23 at 75 °C, 56.38 at 100 °C; Yalkowsky reports 21.5 g/L at 25 °C). Solubility in 99% alcohol 0.72 g/L; in acetic acid 10.9 g/L; insoluble in ether. Soluble in dilute HCl and in alkaline hydroxides and carbonates.
Pharmacopoeial reference	FCC · JP

03Specifications

Specifications

Typical parameters below — the binding version is the Specification Sheet and batch COA we send with your quotation.

Parameter	Specification	Test method
Assay (as-is / dried basis)	—	Titration or HPLC per the applicable monograph
Appearance	—	Visual
Identification	—	IR / specific optical rotation per monograph
Specific optical rotation	—	Polarimetry
Loss on drying	—	Gravimetric
Residue on ignition / sulphated ash	—	Gravimetric
Chloride	—	Per monograph
Sulphate	—	Per monograph
Iron	—	Per monograph
Other amino acids / related substances	—	TLC or HPLC per monograph
Heavy metals (Pb / As / Cd / Hg)	—	ICP-MS or per monograph
Microbiology (TAMC / TYMC / E. coli / Salmonella)	—	USP <61>/<62> or equivalent

A dash means we have no fixed limit to publish for that parameter: it is reported on the batch COA and the limit is agreed with your QA. We would rather leave it blank than invent a number. Full physical, chemical, heavy-metal and microbiological parameters are listed in the Specification Sheet — sent with every quotation.

04Formulation & handling notes

Formulation & handling notes

The practical points our technical team raises with buyers of this material — the things that decide whether a batch behaves in your process.

Leucine is the least water-soluble of the three BCAAs — 24.26 g/L at 25 °C against isoleucine's 41.2 and valine's 88.5 — which is why a 2:1:1 BCAA drink is almost always leucine-limited. If a BCAA concentrate throws sediment, leucine is where to look first.

It is amphoteric in a useful way for process work: soluble in dilute hydrochloric acid and in alkaline hydroxides and carbonates, but only 0.72 g/L in 99% ethanol. Adjusting pH away from the isoelectric point is the practical lever for getting more leucine into solution, not adding co-solvent.

Leucine sublimes and the Merck Index reports decomposition figures ranging from 232 °C to 290 °C, with a melting point cited at 293 °C. It is the most thermally robust of the BCAAs, so it tolerates bar extrusion and hot-fill better than glutamine (which decomposes near 185 °C).

Outside nutrition, leucine's hydrophobic surface makes it a recognised glidant and aerosolisation aid in dry-powder formulation — worth knowing because pharmaceutical-grade demand competes for the same supply and moves the price.

Leucine and isoleucine are isomers with identical formula (C6H13NO2) and molecular weight (131.17). Specific optical rotation distinguishes them: leucine is reported at -10.8° at 25 °C (c = 2.2 in water) and +15.1° in 6 N HCl. Do not accept a COA that identifies either one by formula alone.

Density is reported at 1.293 g/cm3 at 18 °C, but that is the crystal density, not the bulk density that determines whether your scoop volume works. Ask for tapped and bulk density separately if you are scoop-filling.

05Applications

Applications

B2B manufacturing use only — no finished-product or health claims.

BCAA and EAA blends (the dominant single-ingredient use)

Leucine-enriched clinical and sarcopenia nutrition

Protein bars and powders as an amino acid fortifier

Tablet lubricant / glidant in some pharmaceutical formulations

Inhalation powder excipient (leucine is used as an aerosolisation aid)

Capsules and stick packs

06Regulatory status by market

Regulatory status by market

Status of the raw material, stated as conservatively as our sources allow. This is supply-chain information, not regulatory advice — confirm the position for your finished product and destination market with your own regulatory counsel.

Market	Status	Basis
United States	Listed by name in FDA's food-additive regulation for amino acids as 'L-Leucine'. That regulation permits use as a nutrient 'to significantly improve the biological quality of the total protein' of a food, subject to a cap of 8.8 percent by weight of the total protein of the finished food, and to the labelling requirements in paragraph (e). It is not a general-purpose clearance for any food use, and it is not the authority under which dietary supplements are marketed — those sit under DSHEA and 21 CFR part 111.	21 CFR 172.320(a), (b), (c)(4), (e)
European Union	Amino acids are not covered by the harmonised positive lists of Directive 2002/46/EC (Annexes I and II of that Directive cover vitamins and minerals only). Amino acid ingredients are therefore governed by general EU food law plus national rules, with mutual recognition under Article 4 of Regulation (EC) No 764/2008 in practice.	Directive 2002/46/EC (food supplements); national member-state rules
Japan	An Official Monograph titled 'L-Leucine' is listed in the Japanese Pharmacopoeia, Eighteenth Edition. Monograph existence only — no limits transcribed.	JP XVIII, Official Monographs
China	Status as a nutrient fortification substance / food additive under Chinese national standards to be confirmed.	GB 14880-2012 (nutrient fortification substances), GB 2760 (food additives), and NHC new-food-ingredient announcements

07Selected research

Selected research

Peer-reviewed literature on this compound, with linked identifiers so you can read the primary source rather than take our word for it.

These references are listed for scientific context only. They describe published research on the compound; they are not claims about this raw material and not claims about any finished product. Zhicheng Bio makes no medical, health or performance claims.

A quantitative systematic review reported that ingested leucine dose was associated with the magnitude of the postprandial post-exercise muscle protein synthesis response in older adults but not in younger adults, and that no single plasma leucine variable had substantial predictive capacity. Wilkinson K, Koscien CP, Monteyne AJ, Wall BT, Stephens FB. Physiol Rep. 2023;11(15):e15775. PMID 37537134 DOI 10.14814/phy2.15775 Source
A narrative review critically examined the acute and longitudinal literature on isolated leucine and BCAA supplementation for muscular strength and hypertrophy and described the efficacy of BCAAs as an ongoing source of controversy in sports nutrition. Plotkin DL, Delcastillo K, Van Every DW, Tipton KD, Aragon AA, Schoenfeld BJ. Int J Sport Nutr Exerc Metab. 2021;31(3):292-301. PMID 33741748 DOI 10.1123/ijsnem.2020-0356 Source
In six healthy young men, muscle protein synthesis after resistance exercise showed a dose response to ingested whole-egg protein and was maximally stimulated at 20 g, with leucine oxidation significantly increased at 20 and 40 g. Moore DR, Robinson MJ, Fry JL, Tang JE, Glover EI, Wilkinson SB, Prior T, Tarnopolsky MA, Phillips SM. Am J Clin Nutr. 2009;89(1):161-168. PMID 19056590 DOI 10.3945/ajcn.2008.26401 Source
A biochemical review examined the evidence for and against an anabolic effect of isolated branched-chain amino acid intake on muscle protein synthesis in humans and described the evidence for BCAAs alone as equivocal. Santos CS, Nascimento FEL. Einstein (Sao Paulo). 2019;17(3):eRB4898. PMID 31508659 DOI 10.31744/einstein_journal/2019RB4898 Source

08Packing, storage & lead time

Packing, storage & lead time

Standard packing	25 kg bags, cartons or drums
Private packing	Custom packing & labeling available for regular customers
Storage	Cool, dry place, sealed in original packaging
Lead time	Sourced to order — about 1 week to Shanghai port
Shipping	Sea or air consolidation out of Shanghai · FOB / CIF / DDP by lane

09Procurement FAQ

Procurement FAQ

01Why does my BCAA drink go cloudy?

Leucine, nine times out of ten. It is the least soluble BCAA at 24.26 g/L in water at 25 °C, and a leucine-heavy 2:1:1 or 4:1:1 ratio pushes it hardest. Raising temperature or moving pH away from the isoelectric point helps; adding ethanol does not (0.72 g/L in 99% alcohol).

02Can I tell leucine from isoleucine on the COA?

Only by optical rotation or chromatography — the formula and molecular weight are identical. Leucine is reported at about -10.8° at 25 °C (c = 2.2 in water). We will ask the manufacturer to include the rotation on the COA if your QA needs it as an identity test.

03Do you supply pharmaceutical-grade leucine for inhalation or tablet use?

Tell us the monograph and edition you need to comply with and the intended dosage form, and we will go back to the manufacturer. Leucine's use as a glidant and aerosolisation aid has different particle-size and microbiological expectations than a nutritional grade, and it should be specified up front.

04Bulk density — can you give me a number for scoop filling?

The 1.293 g/cm3 in the literature is crystal density and will mislead you. Ask us for the manufacturer's bulk and tapped density on the specification sheet; for scoop-filled products that is the number that decides whether your 5 g scoop actually holds 5 g.

05What is the MOQ for L-Leucine?

MOQ is quote-based and flexible. Tell us your target quantity in the RFQ — for core in-stock SKUs we can usually accommodate both trial orders and multi-tonne volumes.

06Can I get a sample of L-Leucine before ordering?

Yes — samples are available on request for evaluation and lab verification. Mention it in your RFQ and we will confirm the arrangement.

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